INFLORESCENCE. 



77 



237. 



Bracts (J, 5, b). Fig. 237. Cornus Canadensis, with an involucre of four colored 

 biacts. Fiff. 23S. Ilepatica triloba, with an involucre of three green bracts. Fiff. 

 289. Calla palustris, with a colored spathe of one bract, inclosing the spadix. 



147. Brads are evidently of the same nature as leaves, 

 difiering only in tlieir diminished size, and in their position 

 on the flower-stalks, or near the flowers. They are some- 

 times colored as brightly as flowers, as in Painted-cup, or in 

 Balm. AVhen several bracts are arranged in a whorl at the 

 base of the cluster of flowers, an involucre is formed, such as 

 we find in Carrot, and most of the Umbelworts (Fig. 2J:-i). 

 In the Flowering Dogwood the large involucre is colored 

 wliite. 



148. Kext in resemblance to the spike is the sjpadix^ an 

 inflorescence seen in the Calla (Fig. 237), Golden-club (Fig. 

 241), and Cat-tail. It may be defined as a thickened, club- 

 shaped spike, often with a large bract (called sjjathe) at base, 

 as in Jack-in-the-pulpit, or without a spathe, as in Fig. 241. 



147. What sort of leaves grow on the peduncles, if any ? Define bracts 

 What is an involucre? IIow is it in Cornus? 



